public class MaxSubarraySum {
    public static void main(String[] args) {
        // 
        int[] arr1 = {1, -2, 3, 5, -1};
        int[] arr2 = {1, -2, 3, -8, 5, 1};
        int[] arr3 = {1, -2, 3, -2, 5, 1};
        
        System.out.println("数组1的最大子数组和：" + maxSubarraySum(arr1)); // 8
        System.out.println("数组2的最大子数组和：" + maxSubarraySum(arr2)); // 6
        System.out.println("数组3的最大子数组和：" + maxSubarraySum(arr3)); // 7
    }
    
    // Kadane算法实现
    private static int maxSubarraySum(int[] arr) {
        if (arr == null || arr.length == 0) {
            return 0;
        }
        
        int maxCurrent = arr[0];
        int maxGlobal = arr[0];
        
        for (int i = 1; i < arr.length; i++) {
            // 
            maxCurrent = Math.max(arr[i], maxCurrent + arr[i]);
            // 
            if (maxCurrent > maxGlobal) {
                maxGlobal = maxCurrent;
            }
        }
        return maxGlobal;
    }
}
